IR wavelength question

[Coal_Cracker]

Is the T5442T-ZE not sensitive to the 940nm wavelength or is it just recommended to use the 850nm since it has better range?

 

[TonyR]

Most cams are optimized to see 850nm IR; they can see 940 but its effect is reduced so more intensity of 940 is required as compared to the 850. That overall intensity requirement translates to needing more of them in a given area, I would imagine.

I've read estimates that most cams designed for 850 are as much as 80% less sensitive to 940 than 850, meaning you'd need as much as 5x more 940 vs. 850....YMMV

TLDR: that cams sees 940 but it'll take a LOT more of it as compared to 850.

 

[sebastiantombs]

The overwhelming majority of cameras that can see IR are designed to see at 850nm. 940nm may be seen by them but it needs to be at much higher levels than 85nm to get any results. Stick with 850nm. The "range" is essentially the same, the perceived range is significantly different because the cameras aren't designed for 940nm. Stick with 850nm and live with the dull red glow.

 

[Coal_Cracker]

Thanks for the advice. The lights I am looking at come in both 850 and 940. Just want to make sure before I buy them or any others.